Performance Engineer

UK | Full-Time

THE MISSION: SOURCE.DEV http://Source.dev

Our founders spent over a decade at Google shaping the Android operating systems - building and shipping the software that now runs on billions of devices. They didn't just use Android; they led teams responsible for the Android Virtualization Framework, Security, and the Android Runtime (ART).

Through that journey, they saw a quiet but massive crisis: as device software grew in complexity, the tools used to build it remained stuck in the past. Today, a standard Android checkout exceeds 200GB of code, and builds can take hours. This "wait time" is the single biggest tax on innovation.

Source.dev http://Source.dev was founded to reimagine software development workflows for device makers. We’re building a new generation of software tools that make building complex device software feel as simple as building a webpage - starting with SourceFS.

THE CORE PRODUCT: SOURCEFS

SourceFS is a high-performance virtual filesystem designed to turn multi-hour workflows into minutes.

• 10x Faster Builds: Intelligent caching and virtualization that only materializes files when they are actually needed.
• 10x Lower Costs: Enabling a standard 16-vCPU machine to outperform even a 128-vCPU machine.
• True Engineering Productivity: Replaying hundreds of thousands of build steps instantly when inputs match.

THE CULTURAL ANCHOR: OWN IT

We operate with a high degree of trust and a shared value of End-to-End Ownership

"We own our work end-to-end, from spark to finish. It’s about more than just tasks; it’s the dedication to see things through, staying curious to solve problems, thinking from first principles and ensuring we fix our customer’s problems in the best possible way.”

THE ROLE: PUSHING THE SPEED LIMITS OF RUST, LINUX & I/O

We are looking for a Performance / Systems Engineer to join us at Source.dev http://Source.dev. In this role, your primary metric of success is speed. You will dissect execution paths, eliminate kernel-space context-switching costs, optimize memory layouts, and ensure SourceFS runs as close to the hardware limits as physically possible.

WHAT YOU’LL WORK ON

• System Bottleneck Hunting: Profile, trace, and eliminate latency across CPU, memory, and disk I/O bottlenecks in Rust systems code using tools like perf, eBPF, valgrind, and custom microbenchmarks.
• Kernel & File System Tuning: Deep dive into Linux kernel interactions, optimizing FUSE drivers, VFS caches, asynchronous I/O (io_uring), memory-mapped execution, and thread scheduling.
• Memory & Cache Efficiency: Optimize data structures for cache locality, minimize allocation overhead, and eliminate unnecessary memory copies across boundary transitions.
• Benchmarking Infrastructure: Design robust, reproducible benchmarking suites to measure micro- and macro-performance regression in high-concurrency environments.
• Scaling Build Primitives: Squeeze peak performance out of massive build graphs (Android, Yocto, and more) running on high-core hardware configurations.

IDEAL CANDIDATE PROFILE

• The Performance Systems Mindset: You have a deep understanding of computer architecture (CPU caches, memory barriers, SIMD, system calls) and proven experience writing hyper-optimized code in Rust or C/C++.(or other). No prior experience with Rust required, just a willingness to learn is all we are looking for.
• Scale-Obsessed: You have experience with (or a burning desire to fix) large-scale build systems and developer tooling.
• Impact-Driven: You embody the "Own It" mentality - you see a friction point in the developer journey and you don’t stop until it’s gone.
• Curious & Collaborative: You enjoy translating real-world customer problems into robust, production-grade solutions.
• Low Ego, High Impact: Beyond being a brilliant coder, you are a thoughtful and empathetic teammate - someone who leads with kindness
• Feedback Culture Champion: You embrace feedback and provide it thoughtfully; you see open, honest communication as the foundation of great teamwork.

A NOTE ON OUR SEARCH

We are looking for the best talent, wherever it may be. If you’re on the fence about whether you’re a perfect fit, please do apply - we value diverse backgrounds and unique problem-solving approaches.

WHY JOIN SOURCE.DEV http://Source.dev?

• AI-Native Infrastructure: We merge deep systems expertise with AI to solve the "impossible" - using AI to automate complex merges and conflict resolution for the next generation of devices.
• Architect the Future: Have a direct, visible impact on the infrastructure used to build the world’s most advanced hardware.
• Early-Stage Ownership: You’ll have a seat at the table to shape our technical roadmap, product direction, and culture from day one.
• Tier-One Partnerships: Work side-by-side with world-class customers, from global automotive giants to leading cloud providers.
• Elite Engineering Culture: Join a high-trust & passionate team of engineers